Fusion360 MCP Server

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations indicate this is a non-readOnly, non-idempotent, non-destructive operation. The description adds that it creates 'non-parametric' geometry via 'TemporaryBRepManager', which provides useful context about the creation method and persistence characteristics. However, it doesn't explain what 'TemporaryBRepManager' means in practice or how the created box interacts with the modeling environment.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that gets straight to the point. There's no wasted verbiage, though it could potentially benefit from slightly more detail given the complete lack of parameter documentation in the schema.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 6-parameter creation tool with no output schema and 0% schema description coverage, the description is inadequate. It doesn't explain what the tool returns, how the created box integrates into the scene, what coordinate system is used, or provide any examples of typical usage patterns.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

With 0% schema description coverage for all 6 parameters, the description provides no information about what length, width, height, or center coordinates mean. It doesn't specify units, coordinate system, orientation, or how these parameters relate to the resulting box geometry. The description fails to compensate for the complete lack of schema documentation.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb ('Create') and resource ('box primitive'), and specifies it's 'non-parametric via TemporaryBRepManager' which distinguishes it from parametric modeling approaches. However, it doesn't explicitly differentiate from sibling tools like 'create_component' or 'create_cylinder' that also create geometry.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. With many sibling tools for creating geometry (create_cylinder, create_sphere, create_torus, etc.), there's no indication of when a box primitive is appropriate versus other primitives or modeling methods.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.